Which would be the heart rate of a person if the
cardiac output is 5L, blood volume in the ventricles
at the end of diastole is 100 mL and at the end of
ventricular systole is 50 mL?
AI-generated explanation. Check against your textbook.
Explanation:
Cardiac output (CO) = heart rate (HR) × stroke volume (SV). SV = end diastolic volume − end systolic volume = 100 mL − 50 mL = 50 mL = 0.05 L. Given CO = 5 L/min, so HR = CO/SV = 5 L/min ÷ 0.05 L = 100 beats per minute. Therefore, option 2 is correct. The other options would require different SV values: 50 bpm would need SV = 0.1 L, 75 bpm would need SV ≈ 0.0667 L, 125 bpm would need SV ≈ 0.04 L. NCERT emphasizes CO = HR × SV in normal heart function.
🧠 Did You Know?
Stroke volume depends on preload (EDV), afterload, and contractility. EDV here is the amount of blood in the ventricle at the end of diastole.
💡 NCERT Memory Line:
CO = HR × SV, where SV = EDV − ESV; use given CO and EDV/ESV to find HR.
Use of an artificial kidney during hemodialysis may
result in:
(A) Nitrogenous waste build-up in the body
(B) Non-elimination of excess potassium ions
(C) Reduced absorption of calcium ions from gastrointestinal tract
(D) Reduced RBC production
Which of the following options is the most
appropiate?
AI-generated explanation. Check against your textbook.
Explanation:
Use of an artificial kidney (hemodialysis) removes nitrogenous wastes and excess ions from the blood, so it does not cause waste build-up (A) or non-elimination of potassium (B). NCERT explains that kidney disease can disturb vitamin D activation, leading to reduced calcium absorption from the gut, and kidney failure lowers erythropoietin production, reducing RBC production (D). Thus, (C) and (D) are considered correct in this context.
🧠 Did You Know?
In kidney disease, less erythropoietin is made, so doctors sometimes give synthetic EPO to treat anemia associated with reduced RBC production.
💡 NCERT Memory Line:
Kidney failure affects vitamin D activation and erythropoietin production, which can alter calcium absorption and red blood cell formation.
Which of the following glucose transporters is insulin-dependent?
AI-generated explanation. Check against your textbook.
Explanation:
GLUT4 is the glucose transporter that responds to insulin. In adipose tissue and skeletal muscle, insulin triggers the movement of GLUT4 from inside the cell to the cell membrane, increasing glucose uptake. This makes GLUT4 the insulin-dependent transporter. The other options are insulin-independent: GLUT1 is found in many tissues including red blood cells, GLUT2 in liver, kidney, and intestine, and GLUT3 in many tissues. Therefore, GLUT4 (Option 3) is the correct choice.
🧠 Did You Know?
When insulin levels fall, GLUT4 is withdrawn from the membrane, reducing glucose uptake in muscle and fat cells.
💡 NCERT Memory Line:
Insulin-Dependent GLUT4 is present in adipose tissue and skeletal muscle and moves to the membrane in response to insulin.